JP2678793B2 - Tool change control method - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to a method for controlling an indexing operation of a tool magazine and a swinging motion of an exchange arm in an automatic tool changing device for a machine tool.

[Conventional technology]

When designing an automatic tool changer, the tool magazine is arranged as close as possible to the main spindle on the machine tool side due to the demand for downsizing of the apparatus and higher rotation speed of the changing arm. Further, in order to shorten the exchange time, the turning movement of the exchange arm and the indexing operation of the return position of the tool magazine are carried out in parallel in a temporally overlapping state.

[Problems of the prior art]

However, when a large-sized tool is stored in a mixed state in the tool magazine in addition to a normal-sized or small-sized tool, if the swinging motion of the replacement arm and the indexing operation of the tool magazine proceed in parallel, Since a large tool on the side of the exchange arm and a tool on the tool magazine interfere with each other at the approaching position while swiveling, there is a risk of tool damage or tool drop.

[Object of the invention]

Therefore, an object of the present invention is to prevent interference between a large tool on the tool magazine side and a tool on the exchange arm side in an automatic tool changer, and to provide a large tool on the exchange arm side and a tool on the tool magazine side. It is to be able to avoid interference.

[Solution of the Invention]

In view of the above-mentioned object, the present invention executes the swinging motion of the exchange arm and the indexing operation of the return position of the tool magazine in parallel in time when exchanging a tool having a normal shape or a small non-interfering shape. When exchanging a large tool having or interfering with each other, the swinging motion of the exchanging arm and the indexing operation of the return position of the tool magazine are performed independently in time sequence.

[Function of the invention]

According to such control, downsizing of the tool changer,
It is possible to avoid interference between a large tool on the exchange arm side and a tool on the tool magazine side when exchanging a large size tool, while making the most of the advantage of speeding up normal size or small size tool replacement.

〔Example〕

 FIG. 1 shows an outline of the automatic tool changer 1.

The automatic tool changer 1 includes, for example, a rotary tool magazine 3 and a swivel type change arm 4 for changing a plurality of tools 2. The tool magazine 3 has a tool pot 31 detachably provided in a radial storage groove 30 on the outer circumference thereof, and inside the tool pot 31, a large tool 2 other than a normal tool or a small tool 2 can be provided. It is stored at a position unique to the tool 2. This tool magazine 3 has a rotating shaft
The indexing mechanism is rotatably supported in a fixed position by 32
The pitches of the storage grooves 30 are indexed by 33, and the predetermined tool 2 for guiding the tool is guided to the indexing position P1.
Further, this tool magazine 3 is provided with guide means 34 on the back side, and the tool 2 and its tool pot 31 are moved forward or backward at the indexing position P1 in the radial direction, so that a predetermined tool 2 of the exchange arm 4 is moved. Move to the delivery position P2.

Further, the conversion arm 4 has a tool gripping portion 44 at both ends, and is rotatably supported at a fixed position by an arm shaft 41 between the tool magazine 3 and the spindle 6 of the machine tool 5,
The rotation drive means 42 allows the arm shaft 41 to rotate by a predetermined angle, and the advance / retreat drive means.
The arm shaft 41 can also be moved in the axial direction of the arm shaft 41 by 43.

 Next, FIG. 2 shows the configuration of the control system.

The machine tool 5 is controlled by the numerical control device 7 to perform a predetermined machining operation based on a numerical control program. The indexing mechanism 33, the stabilizing means 34, the rotation driving means 42, and the advance / retreat driving means 43 are driven by the exchange control device 8 according to a predetermined exchange program. It should be noted that this exchange control device 8 is a numerical control device 7
It operates based on the replacement command from.

When the exchange control device 8 receives the exchange command from the numerical control device 7, the exchange control device 8 executes at least three types of programs shown in (1), (2) and (3) of FIG. 3 based on the tool exchange control method of the present invention. Then, tool change will be performed automatically.

Fig. 3 (1) shows the tool 2 for the next use of a size that does not interfere.
FIG. 3 shows a replacement control program (1) used when the tool 2 is mounted on the spindle 6 of the tool magazine 3 and the used tool 2 on the spindle 6 side is stored in a predetermined position of the tool magazine 3. (2) shows a tool 2 to be used next time that has a risk of interference or has a large interference from the tool magazine 3 to the spindle 6
Or attach a large tool 2 to the spindle 6,
And a large used tool 2 on the side of the spindle 6 is replaced with a tool magazine 3
2 shows a replacement control program (2) used when the tool is stored in the tool magazine 3 and a large used tool 2 on the spindle 6 side is stored in the tool magazine 3 and does not interfere with the tool magazine 3. The exchange control program (3) used when the tool 2 to be used next time is stored in the spindle 6 is shown.

When the exchange control device 8 receives the exchange instruction from the numerical control device 7, the exchange control device 8 deciphers the instruction content and identifies the exchange control programs (1), (2) and (3).

When the replacement command is the replacement control program (1), the replacement control device 8 first drives the indexing mechanism 33,
The tool 2 to be used next to be commanded is indexed to the indexing position P1, the guiding means 34 is driven, and the tool pot 31 of the commanding tool 2 is moved forward to move to the delivery position P2, and then the rotation driving means 42 and At the same time as the moving arm 4 is operated by the advancing / retreating drive means 43, the indexing mechanism 33 is driven to drive the tool magazine 3 to return the used tool 2 to the return position, that is, the empty tool pot 31 at that position. Determine to P1. At this time, the exchange arm 4 holds the tool 2 to be used next time with one tool gripping portion 44, holds the used tool 2 on the spindle 6 side with the other tool gripping portion 44, and moves the advancing / retreating drive means 43. The tool 2 to be used next time is extracted from the tool pot 31 by using the tool 2, and the used tool 2 is extracted from the main shaft 6 and then rotated 180 degrees by the rotation drive means 42, and then retracted again to re-use the used tool 2
Is stored inside the tool pot 31 which is moving forward, and the tool 2 to be used next time is mounted on the spindle 6. In this way, the pivoting movement of the exchange arm 4 and the indexing operation of the tool magazine 3 are executed in parallel in a temporally overlapping state.

Next, in the case of the exchange control program (2), the exchange control device 8 drives the indexing mechanism 33 to drive the tool magazine 3
The tool 2 to be used next time is indexed to the indexing position P1, the tool pot 31 is then advanced by the guide means 34, and then the replacement arm 4 is rotated. As a result, the tool gripping portion 44 holds a large tool 2 for the next use, the other tool gripping portion 44 holds the used tool 2 of a normal size or a large size, and after removing them, 180 Turn around,
The exchange arm 4 is retracted. As a result, the used tool 2 is stored in the predetermined tool pot 31, and the tool 2 to be used next time is mounted on the spindle 6. After that, the tool magazine 3 is rotated by the indexing mechanism 33, the predetermined storage groove 30 for the used tool 2 is indexed to the indexing position P1, and the used tool 2 is retracted together with the tool pot 31,
The tool magazine 3 is stored in a predetermined storage groove 30 at the index position P1.

Further, in the case of the exchange control program (3), the exchange control device 8 first causes the indexing mechanism 33 to index the position of the tool 2 to be used next time, which is of a normal size, based on the command content.
After indexing to P1, then the guide means 34 advances the tool pot 31, and then the indexing mechanism 33 is driven again to move the predetermined storage groove 30 for accommodating a large used tool 2 to the indexing position P1. By rotating the indexing and exchanging arm 4, the tool gripping portions 44 at both ends grip the tool 2 to be used next time and a large used tool 2 on the main spindle 6 side, and the forward drive means 43 advances it, and then rotationally drives it. The tool 42 to be used next time is mounted on the spindle 6 by rotating the exchanging arm 4 with the means 42 and retreating with the advancing / retreating drive means 43, and the large used tool 2 is stored in the empty tool pot 31 and the tool is used. The pot 31 is retracted to complete a series of tool exchanges.

As described above, in the case of the exchange control programs (2) and (3), the indexing operation of the tool magazine 3 and the turning movement of the exchange arm 4 are independently executed in time sequence. Therefore, the large tool 2 does not interfere with other tools 2 or the like in the process of indexing the tool magazine 3 or in the process of the turning motion of the exchange arm 4.

〔The invention's effect〕

In the present invention, when exchanging a tool having a normal size or a small size without interference, the swiveling motion of the exchanging arm and the indexing operation of the tool magazine proceed in parallel, so the time required for exchanging the tool can be shortened. When exchanging a large tool that may or may cause interference, the indexing operation and the swivel movement of the exchange arm are executed independently without time overlap, so the large tool in the tool magazine and the exchange arm interfere with each other. Without doing so, the risk of tool breakage or dropping can be reliably avoided.

[Brief description of the drawings]

FIG. 1 is a schematic front view of an automatic tool changer, FIG. 2 is a block diagram of a control system, and FIGS. 3 (1) (2) (3) are flowcharts showing respective change control programs. 1 ... Automatic tool changer, 2 ... Tool, 3 ... Tool magazine, 4 ... Exchange arm, 5 ... Machine tool, 6 ... Spindle, 7 ... Numerical control device, 8 ... Exchange control device.

Claims (2)

(57) [Claims] 1. A tool to be used next time is indexed to a replacement position and is mounted on a spindle from a tool magazine by a turning motion of a replacement arm, and a used tool on the spindle side is returned to a unique position of the tool magazine by a turning motion of the replacement arm. In the automatic tool changer to be stored in the
The swivel movement of the exchange arm and the return position of the tool magazine are executed in parallel in time, and when exchanging a tool that has a risk of interference or a size that causes interference, the swivel movement of the exchange arm and the tool magazine A tool change control method characterized in that indexing of a return position is performed independently before and after in time. 2. A tool to be used next time is indexed to a replacement position and is mounted on the spindle from the tool magazine by the turning motion of the replacement arm, and the used tool on the spindle side is returned to the tool magazine by the turning motion of the replacement arm. In the automatic tool changer to be stored in the
The swivel motion of the replacement arm and the indexing of the return position of the tool magazine are executed in parallel in time, and the swivel motion of the replacement arm is performed when a command tool that may or may interfere with the tool magazine is replaced. Indexing of the tool magazine return position after completion of the above, and when exchanging a tool of a size that may or may interfere with the spindle, rotate the replacement arm after completing the indexing of the tool magazine return position. A tool change control method characterized by the above.